Steamboat Springs Union Pacific officials and police are investigating what caused a 16 railroad-car pileup outside of Milner early Wednesday morning.
A Union Pacific train loaded with coal and headed east for Memphis derailed a half-mile east of Milner at about 6 a.m. No one was injured, but the derailment caused extensive damage that shut down the railroad to other trains.
Officials expect cleanup efforts will delay other train traffic until this afternoon.
"The cause is still under investigation," said Mark Davis, a Union Pacific spokesman.
Representatives with the railroad company arrived at the site Wednesday afternoon to begin looking into factors that might have triggered the accident.
Union Pacific crews from Wyoming and Denver are working on detangling the derailed cars with cranes.
"We will work through the night," Davis said. "We estimate the tracks will be open sometime (today)."
Davis said the investigation would entail close inspection of each derailed car and all train parts that might have broken away when the derailment occurred.
"They will detangle all that," he said of the wreckage.
Most of the derailed railroad cars were in one pile.
The railroad cars were carrying coal from Twentymile Coal Co.
Ron Spangler, a spokesman for Twentymile Coal, said the company incurred no losses from the accident.
"Once it leaves our property, it becomes the responsibility of the utility company," he said.
The coal had been purchased by Mississippi Power Co., an electric utility provider for southeast Mississippi.
Mississippi Power will not be able to use the coal carried in the derailed railroad cars, however.
"That coal is dead and dirty," Davis said.
Utility companies don't like to put soiled coal through their boilers, he said, but the product could be sold as scrap material.
Spangler said Twentymile Coal supplies about two trains a day with coal, so the accident would not adversely affect its operation.
"It will probably stop additional shipments up through (today)," he said. "We estimate we might lose five trains over the next day."
Some initial concerns existed about the proximity of power lines to the accident, Routt County Sheriff John Warner said.
Yampa Valley Electric Association was immediately called to shut off the power.
The Sheriff's Office found no criminal activity associated with the derailment.
One other derailment occurred in the same general area about a year ago, Warner said.
"It raises some suspicions, but at the same time, the railroad is dealing with some unstable ground in that area," he said.
The derailment happened on a curve in the tracks, where ground stability is questionable, he said.